Internal-combustion engine.



S. P. HOWE & W. D. KERLIN.

INTERNAL COMBUSTION ENGINE.

APPUBATICIN FILED APR. 1. 191:. 1 301 ,441 Patented Apr. 22, 191E).

4 SHETS-SHET 1' INVENTORJ q/Pf/aw fiama ATTORNEYS mm s S. P. HOWE & W. D. KEHLIN.

INTERNAL comsusnoN ENGINE.

. APPLICATION FILED APR. 7. l9l5. Patented Apr. 22'

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S. P. HOWE 81 W. D. KERLIN.

INTERNAL COMBUSTION ENGINE.

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INTERNAL CUMBUSTION ENGINE.

s m m M" MM P2 M hm 5 m} B i .W M w L SAMUEL P. HOWE, OF MERCHANTVILLE, AND WARD D. KERLIN,

OF CAMDEN, NEW

JERsEY.

IN TERNAL-COMBUS TION ENGINE.

Specification of Letters Patent.

Patented Apr. 22, 1919.

Applicationfiled April 7, 1915. Serial No. 19,645.

To all whom it may concern:

Be it known that we, SAMUEL P. HOWE and WARD D. KERLIN. both citizens of the United States, and residents of the borough of Merchantville and of the city of Camden, respectively, State of New Jersey, have invented certain new and useful Improvements in Internal-Combustion Engines, of which the following is a specification.

This invention relates to internal combustion engines and more particularly to two-cycle internal combustion engines in which the explosive charge is compressed in one cylinder; the compressed charge is then transferred to a second cylinder termed the explosion or power cylinder; and is then exploded and caused to drive forward the piston in the explosion cylinder.

The objects of our invention are to pro vide a construction in which the ignition of the charge may be made to take place after the crank of the explosion cylinder has passed the dead center and advanced on its forward stroke without material diminution of the pressure of the compressed charge; to provide a two-cycle internal combustion engine or motor with a substantially perfect scavenging stroke obtained by the complete travel of the piston in the explosion cylinder on the return stroke; to provide both the explosion cylinder and the compression cylinder with sleeves or cylindrical sliding valves; one for each cylinder and each interposed between the interior of its respective cylinder and the outside of its respective piston, said valves and cylinders being provided with suitable ports for drawing the explosive mixture into the compression cylinder; for transferring the charge to the explosion cylinder, and for allowing the burnt or spent gases to be discharged from the explosion cylinder.

To provide the explosion cylinder and the sleeve valve cooperating therewith with supplemental or auxiliary exhaust ports located at substantially the end of the forward or workin stroke of the piston in the explosion cylin er to permit of the escape of the exhaust gases of high temperature; to provide a construction in which the gases of combustion are allowed to pass out through the main exhaust ports at a tem per-attire lower than that at which they are at the end of the explosion or working stroke. Other objects of our invention will iappear in the specification and claims he- Referring now to the drawings in which the same reference numerals are employed to designate the same parts throughout the various views,

Figure 1 is substantially a longitudinal sectional view of the preferred form or our bodiment of our invention, the section through the cylinders and valve being taken on the line A-AA of Fig. 2;

Fig. 2 is a plan view of the construction shown in Fig. 1;

Fig. 3 is a vertical longitudinal sectional view similar to Fig. 1 of a modified form of our device;

Fig, 4 is a horizontal transverse sectional view of the casing; taken substantially on the line B--B of Fig. 3;

Fig. 5 is a similar section on the line CG of Fig. 3;

Fig. 6 is a similar section taken on the line D-D of Fig. 3;

Fig. 7 is a fragmentary detail view of the eccentric or cam employed for operating the sleeve valves;

Fig. 8 is a detail view of a cam for operating the check or safety valve of the construction illustrated in Fig. 1.

Referring first to the modification shown in Figs. 1 and 2, we provide a casing or housing 1 with suitable journal boxes or bearings 2-2 in which is mounted a crank shaft 3 constituting the main driving shaft in the engine or motor, and which may be provided with a fly and driving Wheel 4. The crank shaft 3 is provided with a crank 5 for operating the compression piston referred to below, and hereafter referred to as the compression crank and a second crank 6, operatively connected to the ex losion piston referred to below, and hereina ter referred to as the explosion crank.

Mounted in the u per part of the casing or housing 1 and a ove the crank shaft 2 are thejcompression cylinder 7 and the explosion cylinder 8. The said cylinders 7 and 8 are preferably arranged with their axes in a vertical plane passing through the lon itudi'nal axis of the crank shaft 3 and witi their longitudinal axes respectively in alinernent with the centers of their respective cranks 5 and 6.

The compression cylinder 7 has mounted within it, and relatively snugly fittin the interior of the cylinder 7, a sleeve va vs 9 arranged to be longitudinally reciprocated within said cylinder 7 by a cam or eccentric 10 mounted on the crank shaft 3. The eccentric 10 is surrounded by an eccentric strap 11 which in turn is connected to an eccentrie'rod 12 the upper end of which is pivotally connected with a projection to a lug 13 on the lower end of the sleeve valve 9. The pivotal connection between the upper end of the eccentric rod 12 and the lug 13 is effected b a bolt or screw 14, the outer end of which carries a substantially square guide block arranged to slide in a guideway formed between. two projecting lugs 16 projecting inwardly from the inner side of the-casing 1. This guide block 15 and the cobperatmg lugs 16 serve to limit the motion of the sleeve valve 9'to a motion longitudinally of the c linder 7, and prevent the sleeve 9 from aving any rotative motion about the axis of the said sleeve or the axis of the c linder coincident there with. The ports in the sleeve valve 9 and cylinder 7 will be referred to below.

Mounted within the sleeve valve 9 is a compression piston 17 having piston rings 17 and within which is secured a pivot pin or bolt 18 upon which is pivotally mounted the upper end 19 of'the compression pitman, said upper end 19 being arranged to telescope within the lower end 20 of the compression pitman, the parts 19 and 20 being capabgleof slight longitudinal motion with respect to each other durin the compression stroke as will be referre tobelow. Around the said upper ortion 19 may be provided a collar 21 ad ustable to any desired osition upon said portion 19 b a suitab e set screw 22. Between said co lar 21 and the upper end of the lower ortion 20 jof the compression cylinder, an coiled around said portion 19 is a compression P 'ing 23.

. The outward longitudinal motionbetween the u per portion 19 and the lower portion 20 o the compression pitman may be limited in any suitable manner as for instance, by providing the upper portion 19 with aprn24 rigid therewith, and the ends of whic roject outwardly and fit within slots 25. ongitudinally. arranged in the lower portion 20 of the compression pitman. In this manner the upper portion 19 is normally held under the influence of the sprin 2 3 so that thepin 24 is in engagement wit 1 the up r end of the ends, of the slot 25 inthe ower portion 20 of the compression itnfian. 'T e lower end 20 of the com ression pitman is pivotally connected to t e compression crank 5 in any usual and well known manner.

liousn Within the explosion cylinder 8 is snugly fitted a sleeve valve 26, the lower end of which is provided with a lug 27 to which is secured a pin or bolt 28 upon which the upper end of the connecting rod 29 is pivotally mounted. The lower end of the connccting rod 29 is provided with an eccentric strap 30 suitably secured to and surrounding the cam or eccentric 31 on the crank shaft 3.

The outer end of the bolt or pin 28 is provided with a substantially square guide block 32, the vertical sides of which engage the inner sides of a pair of guiding lugs 33 projecting inwardly from the casing or g1, the block 32 and guidin In 5 33 operating to limit the, motion of t e s eeve valve 26 to a rectilinear motion parallel with the axis of the cylinder 8 and toprevent any rotative movement of the sleeve valve 26 and the axis of any cylinder 8 or the axis of the sleeve valve 26. In Fig. 1 but one of the lugs 33 is shown but it will be understood that they are mounted and arranged similarly to the lugs 1616, shown in Fi 7. The ports in the cylinder 8 and the s eeve valve 26 will be referred to below.

Within the sleeve valve 26 is mounted an explosion pistontfi l; havin piston rings 34 and within-,whichisprovi ed a pivot or bolt 35 upon which, the-upper end of the explosion pitman36. is .sivotally connected, the

lower end of thesai' explosion pitman being pivotally connected to the explosion crank 6 in any usual and well known manner.

In the compression cylinder 7 and in substantial alinement with the upper end of the interior of the cylinder 7 is the intake port 37 of the cylinder 7, the same being operatively. connected to a 'c'arbureter 38. The

sleeve valve 9 is also provided'with an intake port 39 adapted and arranged at the proper time, as later set forth, to cooperate with the intake "port 37 of the cylinder 7.

The compression cylinder 7 is also pro- 'vided with a transfer port 40 also located in substantial. alinement with the upper end of thejjinterior of thecylinder 7 and the sleevevalve 9 is also. provided with a transfer port 41 located and arranged to be brought into re istration at the roper time in the.cyele of.t e operation of t e compression cylinder with the transfer port 40 of the said cylinder 7, the operation of the same being referred to again and described below.v Similarly the ex losion cylinder 8 is provided with a trans er port 42 arranged to, be put into communication with the transferport '40 of thecylinder 7, said transfer port a2 being substantially in alinement with the up er end of the interior of the explo sion c inder 8. The sleeve valve 26 is also provi ed with a transfer port 43 adapted at the proper time in the cycle of the operation of the explosion cylinder to be brought into registration with the ransfer port 42 of the explosionv cylinder 8.

The explosion cylinder 8 is further provided with a main exhaust port 44 in substantial alinement with the upper end of the interior of the cylinder 8 and the sleeve26 is provided with an exhaust port 45 constructed and arrang d to be brought into registration at the proper time with the said mam exhaust port 44.

T explosion cylinder 8'is'also provided with a s pplemental or. auxiliary exhaust port 46 and the sleeve valve 26 is also provided with a supplemental or auxiliary e-xhaust port 47 which is arranged, at the proper time, to cooperate with the said port 46. Both ports 44 and 4 may be'made to communicate by a passage 4:8 with any suitable exhaust pipe 49 through which the product of the expanded gases may be allowed to escape in the usual manner.

It is to be noted that the upper end ofthe sleeve valve 9 extends for some distance above the intake port 37 and the transfer port 40, the 11 per end being, arranged to slide between the interior of the cylinder 7 nd th outside of he inwa dly projecting cylinder headtqas clearly shown in Fig,- 1 and similarly the upper end of the sleeve l e 26 extends above the inta e port 42 and the exhaust port 44 and' lies betw en the interior of the compression cylinder 8 and the exterior surface of the inwardly extending piston head 51. The length of the said sleeves 9 and 26 is such that when they are in their lowest position, their tops: are above the cooperating ports above mentioned of their respective cylinders.

he explosion cylinder is of course, provided with a spark plug or some other suitable igniting dev ce whereh the charge n the explosion cylinder may ign ted at the proper pomt 1n the stroke of the explosi n cylinder.

We in y also provide between the transfer port 40 and the transfer ort 42a valveifor utting said portslO and 42 into and-out of communication with" each other, this value being in the nature of a safety check and cut-off valve to prevent the back fire ofthe exploding charge into the compression cylinder. The sleeve valives-9 and 26 inpractice, have comparatively little motion relative to their respective cylinders and they move relatively slowly. It thus might happenthat if the valves in the respective cylinders were not adjusted abso utely perfectl'y there might possibly be a communication between the explosion and compression cylinders through the transfer ports at the time the explosion takes place in-the explosion cylinder. To insure a ositive, rapidly acting, cut-ofi' between t'e explosion and compression cylinders during the working stroke of the explosion cylinder, the valve mechanism iiext described may be interposed between the transfer ports 40 and 42 in the compression and explosion cylinders respectively.

Between the cylinders 7 and 8 is provided a cylindrical chamber 53, the upper end of which may be closed by a suitable head 54 and Within which is mounted a piston 55 having therein a chamber 56, the upper end of which is provided with a port 57 arranged to be put into communication with the transfer port 40 and the lower end of which is provided with a port 58 arranged to be put 11111) communication with the transfer port 42. The lower end of the piston 55 is provided with a stem 59 which in turn is secured to the valve-operating rod 60 by a coupling 61 arranged to slide freely through a bearing 62 provided therefor between the cylinders 7 and 8. Above the coupling 61 may be provided a washer 63 adapted to bear against the upper end of the coupling 61 and inter osed between the casing surrounding the ower'end of the piston 55 and said washer 68 is a coiled spring 64 tending to hold the valve operating rod 60 and the parts connected thereto in their lowest positions, as is illustrated in Fig. l of the drawings. Thevalvebperating rod 60 is arranged to have its lower end inengagement with one arm of a ivoted lever 65, the other arm or end of w iich is provided with a roller 66 adapted to be held by said spring 64 in engagement with the outer periphery of a valie-onerating cam 67 mounted on the crank shaft 3.

The lower end of the rod 60 may pass through a suitable bearing 68 provided there or and the lever 65 is preferably pivoted to a bracket 69 connected to the casing or frame work of the motor.

It is, of course, understood that the cylinder heads 50 andfil may be provided-respectively with chambers 70 and 71 throu h which a cooling fluid may be circulated 1n well known manner, and that also the ba an cd piston valve between the two cylinders may be provided with chambers or passages 72,1linoug1h which a cooling fluid may be circulated in any well known manner. The arrangement of the water jacket or cooling chambers of the cylinders 7 and 8 isalso shown in Figs. 3 to 5.

To prevent any leakage of the gases under compression from either the compression 0 linder or the explosion cylinder around t e upper ends of their sleeve valves 9 and 26 respectively, the cylinder heads 50 and 51- are preferably provided with packing rings 73 and 74 respectively, fitting snugly agpmst the interior of their respective sleeve Va V$S- In Fig. 3 is shown a modified form of this invention, the particular differences between the two forms residing in the fact that the compression pitman 19' is made in the form of an ordinary rigid connecting rod of fixed length and that the balanced-piston check and safety valve, which may be desirable under certain conditions and which may be unnecessary under other conditions, is omitted. The operation and timing of the valves in this modification are the same as in the modification shown in Fig. 1.

It should at this point he stated that the cranks 5 and (i are set at substantially an angle of 66 with respect to each other, the explosion crank being substantially 66 in advance of the compression crank, and each crank 5 and 6 being set at substantially 90 in advance of their respective cams or eccentrics 10 and 31 respectively.

When the explosion cylinder 34 is at substantially its uppermost position, the exhaust port 45 in the sleeve valve 46 is moving upwardly and has just passed out of registration with the exhaust ort 44 so that the exhaust port 44 is cut 01?. The port 43 in the sleeve 46 is then moving upwardly and is just beginning to afford communication between t 1e transfer port 42 and the upper end of the cylinder. The compression piston 17 is moving upwardly as is also the compression sleeve valve 9. The port 41 is just beginning to come into registration with the transfer port 40. The intake 37 is closed by the sleeve 9.

From this position the parts move to a position in which the compression piston 17 has moved to substantially its uppermost position, and between these two positions the charge is transferred from the compression to the explosion cylinder. As soon as the transfer port 43 of the explosion cylinder moves upwardly and passes out of registration with the transfer port 42 communication is cut off between the compression and the explosion cylinder. It is at this point that the spark or igniting mechanism is operated to cause an explosion in the explosion cylinder to drive the piston 34 downwardly by the expansion of the burnin mixture or charge.

he piston 34 of the explosion cylinder is then driven downwardly to a position in which the upper end of the piston passes the auxiliary exhaust port 46 in the explosion cylinder. When the port 47 in the sleeve valve 260i the explosion cylinder is in registration with the port 46 the gases of combustion, of high temperature pass directly from the explosion cylinder over the head of the piston through the port 47 and port 46 to the passage 48 communicating wlth the exhaust pipe 49. In this position the sleeve valve 26 is moving downwardly and the piston 34 is near the end of its expansion stroke.

The explosion piston 34 next moves upwardly while the sleeve 26 continues its downward movement and, in the meanwhile, the port 45 has moved down into registration with the main exhaust port 44. This provides an egress for the spent and relatively cooler gases. The ports 42 and 43 are now out of registration as are also the ports 40 and 41, but in moving to this position the intake ports 37 and 39 have been in communication, and, therefore, the compression piston 17 has been permitted to draw in throughthe carbureter an explosive mixture during the simultaneous downward movement of the piston 17. When the piston 17 has almost concluded its downward movement, the port 39 is moving downwardly out of registration with the port 37 so that by the time the piston 17 has moved to its lowest osition, the ports 39 and 37 will be out 0 registration with each other and the intake of explosive mixture will be cut oil.

The explosion piston 34 is now moving upwardly and the sleeve valve 26 is near the end of its downward movement. The compression piston 17 has reached the limit of its downward movement, the exhaust ports 44 and 45ers still in communication with each other, thereby permitting the piston 34 to continue to expelthe spent gases of combus'tion. Communication between the ,two cylinders is, however, cut ofi'by both sleeve valves.

Both pistons and the sleeve valve 26 next move upwardly 'but the sleeve valve 9 is moving downwardly. The explosive mixture is therefore being compressed by the piston 17, but since only the ports 40 and 41 are in communication with each other (the ports 42 and 43 being out of registration) the gas which is being compressed by the iston 17 cannot pass into the explosion cylinder. In the meantime, however, the spent gases are being expelled by the piston 3-4 through the ports 45 and 44 which are at 'this t me in registration with each other,

When the explosion piston is near the end of this upward stroke, the ports 44 and 45 are still in communication, but the sleeve 26 is relatively rapidly moving upwardly so that by the time the piston 34 reaches its up ermost position, the main exhaust ports wi 1 be closed. The transfer port 43 is still out of communication with the transfer port 42 but it is also rising so that at the time the piston reaches its u ermost position, the ports 42 and 43 will egin to be in IBElStlfltiOn with each other. In the meanw ile, the piston 17 is also moving upwardly; the ports 40 and 41 are still in communication with each other, and the intake port 37 is cut off by the sleeve 9. The pistons 34 and 17 and the sleeves 9 and 26 are at this point in the description of their operation approaching the position first above described and when they reach said positions the cycle will be completed.

Now referring further to the form of the invention illustrated in Fig. 1, wherein there is provided a balanced safety valve between the transfer ports 40 and 42, and also referring lo the cam shown in Fig. 8, it is to be noted that the valve is quick acting and is in the position shown in Fig. 1 during only substantially 66 of the revolution of the crank shaft; that is to say, the valve is open for only a relatively short time to afford communication between the transfer ports in the respective cylinders. At other times communication between the two cylinders is positively cut otf by the auxiliary balanced piston valve.

In this manner. the piston valve is opened only during the transference of the explosive mixture from the compression cylinder to the explosion cylinder.

Althou h it is desirable to have the pressure to which the explosive mixture is subjected during its transfer from the compression to the explosion cylinder, practically or substantially constant, it will be apparent that in the form of engine shown in Fig. 3, that the explosive mixture will for a short period be subjected to a somewhat higher pressure than is necessary for the mere transference of the mixture.

At this time in the cycle of the operation of the device and immediately thereafter, the piston in the explosion cylinder is moving downwardly relatively slowly although its speed is a constantly increasing speed, while the piston in the compression cylinder is moving upwardly relatively rapidly although its speed is constantly decreasing. By the time, however, the pistons have reached the positions in which the charge has been transferred to the explosion cylinder, the piston in the explosion cylinder is moving much more rapidly downwardly than the piston in the compression cylinder is moving upwardly; in fact, the piston 1n the compression cylinder is substantially stationary at that instant. During the transfer of the explosive mixture from the compression cylinder to the explosion cylinder, the explosive charge which is trapped and held between the cylinders is subjected to a slightly higher'degree of compression than is absolutely necessary for t e mere transference of the charge, and to a higher degree than the gases are subjected at the time of their explosion in the explosion cylinder. Although this action does not substantially or materially interfere with an cflicient operation of the engine or motor, it might be desirable to relieve the mechanism to some extent of the work required to unduly compress the charge and, for that pur pose. in their preferred form or embodiment of this iiwention, the pitman of the compression cylinder is made in two parts telescop ing with each other, as previously described and as illustrated in Fig. 1, with a compres sion spring interposed between the upper part 19 and the lower part 20. Any standard coil spring designed to yield under the pressure to which the explosion mixture is to be subjected at the time of the explosion thereof in the explosion cylinder may be employed for the purpose.

In this cmistruction, when the explosive mixture in the compression cylinder has been compressed to the pressure at which the same will be exploded in the explosion cylinder, the spring will thereafter yield and permit a relative movement between the two parts of the compression pitman, and in this way the gas entrapped between the two pistons will not be subjected to a pressure substantially greater than the' pre determined pressure at which it is desired to have the explosive mixture subjected just prior to its explosion.

While we have above described two structures in which our invention is embodied We do not wish to be construed as limited to the exact detail of the devices illustrated in the drawings of this case as it is obvious that slight ehan es may be made in the arran ement and disposition of the parts thereof without departing from the spirit and scope of this invention.

Having thus described our invention, what we claim and desire to protect by Lettcrs Patent of the United States is:

1. In a two-cycle internal combustion englue, the combination of a compression cylindcr, a cylindrical valve mounted therein, a compression piston mounted within said cylindrical valve, an explosion cylinder, at cylindrical valve mounted therein, a mounted within said cylindrical valve in said explosion cylinder, a crank shaft, two cranks carried by said shaft and two connecting rods eachconne'eti-n-g a pistonand one of said cranks respectively, a pair of eccentrics on said shaft and an eccentric rod connectin each eccentric with one of said cylindrical valves respectively, the crank for the explosion piston being set in advance of the crank for said compression piston,- nieake, transfer and exhaust ports in said cylinders and in said cylindrical valves arranged at one end of said cylinders, an auxiliary eutotf valve interposed between the exhaust portsof said cylindric'ai valves, and wine iliary exhaust ports in the explosion c li'ndei: and the cylindrical valve mounted t ere in, arranged near the opposite end of said explosion cylinder and arranged to he in communication with each other when the explosion piston is near the end of its work ing stroke.

2. In a two-cycle internal combustion en v tween said transfer ports and means to op-' glue, the combination of a compression cylinder, a cylindrical valve mounted therelm a compression piston mounted within said cylindrical valve, an explosion cylinder, a cylindrical valve mounted therein, a piston mounted within said cylindrical valve in said explosion cylinder, a crank shaft, two cranks carried by said shaft and two connectin rods, each connecting a piston with one of said cranks respectively, a pair of eccentrics on said shaft, and an eccentric rod connecting each eccentric with one of said cylindrical valves respectively, an auxiliary cutoff valve interposed between the transfer ports in said cylindrical valves of the cylinders and arranged to establish and cut off communication between said transfer ports, and means to operate said cutofl' valve to cut off communication between said cylinders at all times except during the latter part of the compression stroke of the compression cylinder and the first part of the explosion stroke of the explosion cylinder.

3. In a two-cycle internal combustion engine, the combination of a compression cylinder, a cylindrical valve mounted there1n, a compression piston mounted within said cylindrical valve, an explosion cylinder, a cylindrical valve mounted therein, a piston mounted within said cylindrical valve in said explosion cylinder, a crank shaft, two cranks carried by said shaft and two connecting rods each connecting a piston and one of said cranks respectively, a pair of eccentrics on said shaft and an eccentric rod connecting an eccentric with one of said cylindrical valves respectively, an auxiliary cut-off valve interposed between the transfer orts of the cylinders and arranged to estafilish and to cut off communication between said transfer ports and means to operate said cut-off valve to cut off communication between said cylinders at all times except durin the latter part of the compression stro e of the compression p ston andthe first part of the explosion stroke of the explosion cylinder.

4. In a two-cycle internal combustion engine, the combination of a compression cylinder, a cylindrical valve mounted there1n, a compression piston mounted within said cylindrical valve, an explosion cylinder, a cylindrical, valve mounted therein, a piston mounted within said cylindrical valve in said explosion cylinder, a crank shaft, two cranks carried by said shaft and two connecting rodseac connectin a piston and one of saidcranks respective y, an auxiliary balanced cut-off valve interposed between the transferports of both cylinders arran ed to establish and to cut off communication ecrate said cut off valveto cut off communication between said transfer ports at all times except during the latter part of the compression stroke of the com ression piston and the first part of the exp osion stroke of the explosion cylinder.

5. In a two-cycle internal combustion engine, the combination with a compression cylinder, a cylindrical valve mounted therein, a compression piston mounted within said cylindrical valve, an ex losion cylinder, a cylindrical valve mountc therein, a piston mounted within said cylindrical valve in said explosion cylinder, a crank shaft, two cranks carried by said shaft and two connectin rods each connecting a piston and one 0 said cranks respectively, a pair of eccentrics on said shaft, eccentric rods connecting each eccentric with one of said cylindrical valves respectively, and a balanced and cut-ofi' valve located between the trans fer ports of both cylinders and arranged to cut off communication between said cylinders just prior to the explosion of the charge in said explosion cylinder and to hold said transfer ports out of communication with each other at all times except during the transfer of the charge from the compression cylinder to the explosion cylinder.

6. In an internal combustion engine, the combination of a compression cylinder having intake and transfer ports near the head end thereof, a longitudinally reciprocatory cylindrical valve fitted within said cylinder, a piston fitted Within said cylindrical valve. a cylinder head secured to said cylinder and projecting into the head end of said cylindrical valve, a packing ring between the interior of said cylindrical valve and the exterior of the end of said cylinder head projecting into said valve, and an explosion cylinder, a transferpassage connecting said compression and explosion cylinders provided with a regulating valve, a transfer and a main exhaust port near the head end of said explosion cylinder, a lon 'tudinally reciprocatory cylindrical valve fitted within said explosion cylinder, a piston fitting within said last mentioned cyllndrical valve, a cylinder head secured to said explosion cylinder and projectin into the interior of the head end of said first mentioned cylindrical valve, and a packing ring fitting between the interior of said last mentioned cylindrical. valve and the exterior of the end of said cylinder head of said explosion cylinder last mentioned projecting into said valve.

7. In a two-cycle, internal combustion enine, the combination of a compression cylinder provided with inlet and outlet valves, a compression piston located therein, an explosion cylinder rovided with inlet and exhaust valves, a piston located therein, with a transfer passage connecting said compression and explosion cylinders and an auxiliary cut-off valve located in said passage and adapted to cut off communication be tween said cylinders at all times except during the latter part of the compression stroke of the compression piston and the first part of the explosion stroke of the explosion piston.

8. In a two-cycle internal combustion engine, the combination of a compression cylinder provided With inlet and outlet valves, an explosion cylinder provided with inlet and exhaust valves, pistons in said compression and explosion cylinders and a transfer passage connecting said compression and explosion cylinders, provided with an auxiliary balanced cut-ofl' valve, and means to operate said cut-off valve to cut off the communication between said cylinders at all times except during the latter part of the compression stroke of the compression piston and the first part of the explosion stroke of the explosion cylinder.

9. In a twocycle internal combustion engine, the combination of a compression cylinder provided with inlet and outlet valves and a compression piston With an explosion cylinder provided with inlet and exhaust valves and a power piston, a transfer passage connecting said cylinders, a valve in said passage, and means for transferring the compressed mixture at a substantially constant pressure from said compression cylinder to said explosion cylinder.

10. In a two-cycle internal combustion engine, the combination of a compression cylinder provided with inlet and outlet valves, an explosion cylinder provided with inlet and exhaust valves, pistons in said cylinders, a crank shaft, connecting rods between the crank shaft and pistons, a transfer passage connecting said compression and explosion cylinders and provided With an automatically operated valve, said compression piston connecting rod being yieldable whereby, when said automatic valve is open the explosive mixture in the compression cylinder is transferred at substantially constant pressure to said explosion cylinder.

11. In a two-cycle internal combustion engine, the combination of a compression cylinder provided with inlet and outlet valves and a piston, and an explosion cylinder provided With inlet valve and a power piston, said explosion cylinder being provided with a main exhaust port adjacent the head end of said explosion cylinder and an auxiliary exhaust port located near the crank end of said explosion cylinder, a transfer passage connecting said compression and explosion cylinders, and a valve for said explosion cylinder for controlling said inlet port and said main and auxiliary exhaust ports.

12. In a two-cycle internal combustion engine, the combination of a compression cylinder and an explosion cylinder With a transfer passage connecting the same, an inlet and outlet valve for said compression cylinder and a piston therefor, a piston in said explosion cylinder and an inlet therefor and a main and an auxiliary exhaust port for said cylinder, said main port being located near the head end of said explosion cylinder and said auxiliary port being located near the crank end of said cylinder, means for transferring the compressed mixture from said compression cylinder to said explosion cylinder after the power piston has passed a dead center, means for igniting said explosive mixture after said piston has passed said dead center and means for operating said main and auxiliary exhaust valves.

In Witness whereof, We have hereunto set our hands this 31st day of March, 1915.

SAMUEL P. HOWE. IV. D. KERLIN.

\Vitnesses Gno. F. LAMMEY, M. M. DEVINE.

Copies of this patent may be obtained for five cents each, by addressing the "Commissioner of Patents, Washington, D. 6. 

